We've dealt with the same thing. I don't recommend the poison traps becasue the mice will take it and may end up dying and rotting in your walls. We had a horrible stench in the kitchen and couldn't figure out why. When DH had to replace the bottom of a cabinet due to a leak, we found several carcasses under the cabinet. Once we got rid of the carcasses, the stench went away. For that reason, I stay away from the poison bait traps.
Someone else posted that they made sure every scrap of food was sealed and put away so that the mice wouldn't have any food to eat. That helps big time. Plus find every tiny hole into your house and plug it/seal it/block it. Mice can get into the tiniest crevices. Put traps outside around the foundation of your house so that you'll catch them before they get in.
Sorry to say it, but the most effective thing we tried was the standard snap traps with PB. I know it seems cruel, but which do you want safe, happy mice or a mouse free home? You have to remember that mice can bring in fleas and disease too.
At first we caught two or three a day, then it tapered off to one every couple of days. Finally we stopped getting them, but it took several weeks. Also we had to set new traps every spring and fall. Fall was worse. By being watchful and getting an early start with the traps, we finally managed to keep them out of the house, but we had to be ever vigilant.
Eventually you'll get on top of the problem, be persistent. Good luck!
Claude
"Age is a question of mind over matter. If you don't mind, it doesn't matter." Satchel Paige